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    <title>Document</title>
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<script>
    //Math.round()四舍五入的操作
    var result1 = Math.round(1.3);
    console.log(result1);

    var num = 2.16;
    num =num *10;
    var result2 =Math.round(num);
    reslut2 =result2/10;
//向下取整 math.floor   向上取整 math.cell
    var result3 =Math.floor(1.6);
    var result4 =Math.ceil(1.3);
    console.log(result3,result4);


    
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